DeBrock et al., "A Survey of Current Developments in Surface Tension Devices for Propellant Acquisition", Journal of Spacecraft and Rockets, Vol. 8, No. 2, February 1971, pp. 83-98, shows a number of propellant management devices for spacecraft liquid propellant tanks. For example, FIG. 4 shows a system of screened galleries, formed using rectangular channels, extending throughout the interior of the tank. In the present invention, screens or other relatively closed portions 10 of liquid communication channels 2 do not extend all the way into the upper half 3 of the tank 1; and the liquid communication channels 2 are preferably V-shaped.
U.S. Pat. No. 3,923,188 shows another type of rectangular-cross-section screened gallery propellant management system (PMS) in which the screens extend all the way into the upper reaches of the tank. Unlike the present invention, the reference device has no flat spin recovery capability and no capability for adverse acceleration conditions when the propellant quantity is small.
U.S. Pat. No. 4,272,257 shows a propellant management system having liquid-vapor separators inserted into galleries. The separators, which serve the same role as screens, extend all the way into the upper half of the tank. This presents the same disadvantages as with those prior art devices using screens, which disadvantages are overcome by the present invention as will be explained infra. The reference device does not disclose a flat spin capability as in the present invention. In col. 1, lines 35-36, the reference patent mentions triangular-shaped port openings in prior art screened gallery PMS's.
U.S. Pat. No. 4,399,831 shows a propellant management system having rectangular-cross-section screened galleries extending all the way into the upper half of the tank. Chamber 27 surrounding solid 26 is used for a bubble trap, but this structure does not perform all of the functions, such as liquid communication, as bubble trap assembly 9 of the present invention.
U.S. Pat. No. 4,553,565 shows a propellant management system using vane channels (FIGS. 5A and 5B). The channels have less propellant retention and acquisition capability than the V-shaped channels 2 described in the present specification. The reference device does not have a flat spin recovery capability of a spinup capability as in the present invention.